No.

Charcoal will jsut suck the water out of the soil and rock pebbles will sit there like dumb rocks do.

Go to a NURSERY, not a hardware store and ask for STARTER grow medium. You want light, airy and fluffy stuff.

If a big bag is heavy to carry, its too heavy for optimal growing.

I recommmend PRO MIX...it meets all the qualifications of the MJ plant.

Requires often watering though.